fix: edit_row default {} → None (Jinja2 truthy bug), init_db with app_context, add README

app.py

@@ -86,7 +86,7 @@ def index():
         return redirect(url_for("index"))
 
     # --- GET: список + форма редактирования ---
-    edit_row = {}
+    edit_row = None
     edit_id = request.args.get("edit")
     if edit_id:
         cur.execute(
@@ -112,5 +112,6 @@ def index():
 
 
 if __name__ == "__main__":
-    init_db()
+    with app.app_context():
+        init_db()
     app.run(host="0.0.0.0", port=int(os.environ.get("PORT", 5000)), debug=False)